Sci Am ranks fusion as a longshot this century

While I sometimes find myself at odds with the conclusions that Wired writers and editors reach on energy matters (Have you got something truly massive? Lots of blinky lights? With an impossibly long-lived waste stream? They're probably for it.), I frequently find myself in stride with Scientific American.

Another case in point reached my mailbox this week in the magazine's collection of shorts, “12 EVENTS That Will Change Everything,” in which a cast of writers and editors list the most “dramatic new events” that could shake up the human reality this century. Included in the bunch are human cloning, hidden dimensions, ET, and a nuclear weapon “exchange” (and by that we don't mean you take mine and I take yours).

There is also a simplistic “likelihood” scale intended to suggest whether the possibilities are considered a sure thing, a long shot, or somewhere between the poles.

Among the long shots is nuclear fusion.

Some of our readers may remember our days of rampant nuke obsessing, circa 2009. In a series of articles, we laid out a less-than-flattering portrait of the fuel chain of nuclear power: from mining contamination to the problem of an “eternal” waste stream.

One UT researcher, Swadesh Mahajan, stood up for a hybrid fusion-fission reactor as a possible waste solution; others, like one old-school Hanford nuke man who jumped to solar in the 1970s, scoffed.

While nuclear fusion has promised and failed for decades to deliver a working utility-scale reactor, a hybrid fission-fusion reactor is within reach, Mahajan insists. He describes it as “a fast reactor on viagra.” â?¦ But even Mahajan admits a working model of his team's hybrid reactor is still 15 years away. “The important thing is not that we start destroying the waste today,” he says. “The important thing is that we tell the public right now that we have the means of destroying it on which we can depend.”

Mahajan's claim earns another layer of sketchiness when laid against the Sci Am article when we read, “According to the old quip, a practical fusion reactor will always be about 20 years away. Nowadays that feels a bit optimistic.”

After describing the challenges of fusion â?? 16 years minimum before testing can begin, time to design and construct a prototype, serious financial constraints that would limit any construction after that â?? the fusion-fission approach is described in brief with optimistic predictions similar to Mahajan's. Then the whole to-do concludes with flourish, “In other words, a practical fusion reactor is only about 20 years away.”

So the next time a nuke booster says they trust technology to handle the waste. Ask them which technology, because it most likely won't be fusion. Not this century, anyway.

`View the full Sci Am interactive version of '12 Things' and get a fast-and-loose explanation of fusion, description of the coming polar-ice meltdown, and where to hide when the machines wake up.`